Microwave attenuation measurement as a function of moisture content and density of material for moisture determination over wide range

摘要

A method is proposed to measure the microwave attenuation as a function of moisture content and density for moisture determination of soft, water-absorptive material. The mea- surement result with sawdust shows that the attenuation can be approximated as a linear function with respect to the density when the moisture content is constant. For constant density, the attenuation can be approximated as a quadratic function with respect to the moisture content in low moisture content range below about 30/100(d.b)and as a linear function with respect to the moisture content in high range above this moisture content.